A typical rotary compressor includes a cylinder, a roller which rotates in a cylinder chamber of the cylinder, a head component having an ejection port by which refrigerant compressed by the rotation of the roller is ejected, and a muffler component which is provided so that a muffler space is formed between the head component and the muffler component. FIG. 14 schematically illustrates a sealing structure between a head component and a muffler component according to a conventional example. As shown in FIG. 14(a), a conventional sealing structure 650 between a head component and a muffler component is arranged so that the muffler component 639 is fastened to a side wall 638d of the head component 638 by plural bolts 642, and a muffler space is formed by blocking off a recess 638A formed in the head component 638.
However, the conventional sealing structure 650 of FIG. 14(a) is disadvantageous in that, when a mounting surface of the muffler component 639 and a mounting surface of the head component 638 are not flat enough, a gap is formed between a boss portion 638c of the head component 638 and the muffler component 639 as shown in FIG. 14(b), and refrigerant leaks out from the gap.
In consideration of the above, recent developed arrangements prevent the leakage of refrigerant through the gap by preventing the formation of the gap between the boss portion and the muffler component in such a way that the precision of the mounting surfaces of the muffler component and the head component is improved by machining.
However, even if the mounting surfaces of the muffler component and the head component have been subjected to machining, as shown in FIG. 14(c), refrigerant introduced through an ejection port (not illustrated) of the head component 638 causes a pressure P1 of the muffler space to be higher than a pressure P2 in the closed container of the compressor, with the result that the refrigerant leaks out from the border between the boss portion 638c and the muffler component 639, which part is not fastened by the bolts 642. The leakage of refrigerant induces increase in vibration and noise of the compressor and obstructs lubricating oil from being supplied to a slide portion because the lubricating oil stored in the bottom portion of the closed container foams, and hence the reliability of the compressor is deteriorated.
To solve this problem, various structures have been proposed to prevent refrigerant from leaking from the border between the boss portion and the muffler component (see e.g. Japanese Unexamined Patent Publication No. 215993/1990). A rotary compressor disclosed in Japanese Unexamined Patent Publication No. 215993/1990 is arranged so that the leakage of refrigerant from the border between the boss portion and the muffler component is prevented by providing a conical claw washer as a gas sealing member between the boss portion and the muffler component.